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UW Students Research Value of Satellite Images for Monitoring Wyoming Resources

May 18, 2012 — Students at the University of Wyoming found that aspen had
budded earlier in a drought year, and that surface area estimates from
satellite images matched well with corresponding water levels in Woodruff
Narrows Reservoir near Evanston.

Other students used information derived from remotely sensed
images to monitor crop growth on a southeast Wyoming wheat farm and the effects
of the 2004 Basin Draw fire in northeast Wyoming. The research taught students
how to use satellite images and its effectiveness.

Every spring semester, three to five students -- in the
Department of Ecosystem Science and Management in the UW College of Agriculture
and Natural Resources -- conduct research using remotely sensed data on a topic
of their interest, says Ramesh Sivanpillai, research scientist in the Wyoming
Geographic Information Science Center. He teaches the college's digital image
processing for natural resources management course.

"Most of these students select the farms or ranches owned by
family members or forests and public land they have worked on during summer
months," he says. "Familiarity about their study areas provides them a unique
advantage when analyzing and interpreting satellite images, and for conveying
the findings of their study to the landowners or agencies."

Matthew Thoman of Riverton worked on a dryland winter wheat
farm east of Cheyenne and was familiar with the fields. By processing Landsat
images from the growing seasons of 2007 and 2009, he found growth variations
within fields -- despite higher soil moisture levels in 2009 than 2007.

He will share the information with the producer, who could
devise plans to correct the deficiencies, Sivanpillai says.

Brandt Schiche of Buffalo used Landsat images to glean
information about surface area changes on Woodruff Narrows Reservoir. Water
from the reservoir is used for irrigation, recreation and industry, and is
shared between Utah and Wyoming.

"He found a significant relationship between the surface
area estimates derived from Landsat images and the corresponding water levels
in the reservoir," Sivanpillai says.

Jason Pindell of Wheatland used MODIS (Moderate Resolution
Imaging Spectroradiometer) data to assess differences in the growing pattern of
aspen stands in the Medicine Bow National Forest. His research showed aspen put out leaves
relatively earlier (bud-burst) in a drought year (2002) in comparison to the
bud-burst in a normal year (2009).

Orin Hutchinson of Newcastle had worked with the U.S. Forest
Service managing wildfires. He evaluated indices derived from Landsat images
that highlighted burned (immediately) and revegetated (few years later) areas after
the 2004 Basin Draw fire northwest of Aladdin in Crook County. The fire burned
more than 4,500 acres in three days, but its impact and severity varied
throughout the landscape.

"His results pointed out that burn severity index values
were in good agreement with the data collected in the field," Sivanpillai says.
"However, extraneous factors, such as precipitation and management practices,
influenced the vegetation regrowth, limiting the effectiveness of satellite
data for monitoring regrowth after several years."

Students presented their findings during UW's recent
Undergraduate Research Day.

Photo:Orin Hutchinson analyzes Landsat images acquired after a
wildfire on the Wyoming side of the Black Hills National Forest. (UW Photo)